1. Field of the Invention
The present invention concerns a method and a device for forming fiber packs from a fiber strand, in particular fiber packs which are used for manufacturing brushes.
2. Description of the Related Art
It is known that the fibers for forming brush hairs are packed into fiber strands consisting of parallel fibers which are kept together by means of a cover. These fiber strands, which usually have a diameter of some 5 cm and a length of 1 to 2 m, are cut in parts of the required length at a later stage. Thus are obtained packed fiber packs which can be supplied to a brush manufacturing machine, where the cover is removed from the fiber packs and where the fibers are provided in the fiber magazines.
According to U.S. Pat. No. 4,680,850 of the applicant, the cover of the fibers which are cut at a specific length is removed by partially cutting in the cover and by folding it, such that the fibers are set free over a certain length, and by subsequently grasping the fiber pack with a clamp on the part which has been set free, after which the cover is entirely removed.
From German patent No. 195.25.808 it is known to partially turn up the cover of each part to be cut off from such a fiber strand before cutting off the part concerned. Thus are obtained fiber packs cut at a specific length whose fibers are still kept together by the cover, but which also have a part which has been set free which makes it possible to put a clamp on the fiber pack, after which the cover can be entirely removed from the fiber pack.
The present invention aims an improved method and device for making fiber packs from fiber strands which are new and which moreover offer several advantages.
To this end, the invention aims a method for forming fiber packs for manufacturing brushes from a fiber strand, whereby fiber packs are formed from a fiber strand which is provided with a cover by cutting off parts of this fiber strand, characterized in that, before such a part is cut off, the cover is entirely removed from said part.
As the cover is already entirely removed from the part to be cut off before this part is cut off from the fiber strand, this offers the advantage that one does need to be particularly cautious when removing the cover, as the fibers of the fiber pack to be formed are still connected to the rest of the fiber strand at that time and thus cannot fall apart.
Also according to the invention, the time-consuming intermediate treatment, which is necessary in the known embodiments in order to remove the cover of the fiber pack which has already been cut off, is excluded.
As the entire fiber part to be cut off is set free according to the invention, the cover does not form an obstacle for providing a clamp, which is the case with the above-mentioned known techniques, as the fibers of the fiber pack are still surrounded by a part of the cover while the clamp is being provided, so that there is little place for the clamp.
Another ensuing advantage consists in that the length of the fiber packs to be cut off is no longer restricted by the manipulations which have to be carried out thereupon later on in order to remove the cover, so that fiber packs with very short fiber lengths, smaller than 2 cm, can be formed and be processed.
It is clear, however, that the fibers to be cut off have to be clamped or inserted in an appropriate device before they are cut off, so that the fiber pack does not fall apart after the fibers have been cut off. Preferably, the fibers of the above-mentioned part are held to this end in a clamping device, after the cover has been removed from this part, but before the part is cut off, so that they can be carried off directly for further manipulation by means of this clamping device.
According to the most preferred embodiment, the cover is systematically removed as the parts are being cut off. As a result, the fibers of the remaining part of the fiber strand remain well arranged.
According to a practical embodiment, the cover is removed by systematically removing it as of the end where the above-mentioned parts are being cut off, whereas the cover on the remaining part of the fiber strand is left untouched.
In particular, the cover is preferably removed by cutting it in the longitudinal direction at one or several places on the perimeter and by carrying off the cut cover sideways.
According to a variant, the cover is removed by unwinding it from the fiber strand.
Although the cover of the rear part of the fiber strand is preferably left untouched, as described above, it is not excluded to remove the cover by either shifting it backward, or by shifting it as a whole like a cylinder, or by turning it up in a zigzag way.
According to a special embodiment, a fixed device is used to remove the cover; the fiber strand is moved through this device; and the fiber strand is lowered through the above-mentioned device, making use of the gravitational force, either or not with the help of additional means.
Practically, the cut-off fiber packs are then straightened by beating them or making them vibrate in an auxiliary device, between two stops, such that all the ends of the fibers are situated in one and the same plane.
The invention also concerns a method for manufacturing brushes, characterized in that the brush fibers are obtained from fiber packs which are formed according to the above-described method.
Further, the invention also concerns a device for forming fiber packs from a fiber strand according to the known method, characterized in that it at least consists of supply means for a fiber strand; means for removing the cover from the fiber strand; a stop for the end of the fiber strand; a cutting device for cutting off parts of the fiber strand which operates in between the means for removing the cover from the fiber strand and the above-mentioned stop; and a clamping device for holding the above-mentioned parts.